The present invention relates generally to electronic devices and, more particularly, to a transition region for use between an electron tunneling junction and a planar antenna connected therewith. The transition region is compatible with a variety of device configurations and antenna structures.
Prior art planar antennas are used at various frequency ranges such as, for example, microwave, millimeter wave and infrared frequencies to couple energy between a current pathway and free space. The planar configuration of these antennas enables ease of fabrication using electrically conductive layers formed on non-electrically conductive substrate materials. High speed electron tunneling device technology, developed by the Phiar® Corporation of Boulder, Colo., incorporates the advantages of the planar antenna with innovative tunneling junction structures, in order to provide high speed electron tunneling devices connected with one or more planar antennas for receiving or emitting electromagnetic radiation. Additionally, Phiar Corporation has developed modified planar antenna designs for use with electron tunneling devices. For example, U.S. patent application Ser. No. 09/860,988, now U.S. Pat. No. 6,534,784, and U.S. patent application Ser. No. 09/860,972, now U.S. Pat. No. 6,563,185 disclose high speed, metal-insulator electron tunneling devices capable of operating at frequencies even as high as in the optical range. U.S. patent application Ser. No. 10/103,054, now U.S. Pat. No. 7,010,183, and U.S. patent application Ser. No. 10/140,535, now U.S. Patent No. 7,177,515, disclose traveling wave configurations of the electron tunneling device. U.S. patent application Ser. No. 10/265,935, now U.S. Pat. No. 6,664,562 and U.S. patent application Ser. No. 10/335,731, now U.S. Pat. No. 7,019,704 describe improved antenna configurations suitable for use with these electron tunneling devices. U.S. patent application Ser. No. 10/337,427, now U.S. Pat. No. 7,126,151 discloses electron tunneling devices coupled with waveguides and placed on chips while providing, for example, inter- and intra-chip optical interconnections. In addition, U.S. patent application Ser. No. 10/462,491, now U.S. Pat. No. 6,967,347, describes the use of terahertz carrier frequency signals to provide an interconnection between components on a chip, between chips and the like. All of the aforementioned patents and patent applications are incorporated herein by reference in their entirety.
This overall, commonly owned group of patents and applications may be referred to collectively herein as the Phiar Patents. Since the Phiar Patents are considered to provide significant advantages over the then-existing state-of-the-art, the present disclosure is considered to describe still further highly advantageous advancements, as seen below.
There are numerous examples in the literature of transmission line taper designs for a single type of transmission line, such as an exclusively CPS or PP line. For example, Klopfenstein describes a taper design in which the transition between known, highly mismatched impedances may be accomplished in a very small distance (on the order of wavelengths) compared to other types of tapers while providing only small and readily controllable reflections in the passband [1]. The theory of Klopfenstein has been used in various applications such as, for instance, satellite antenna design [2], square kilometer antenna (SKA) project for outer space monitoring [3] and microstrip transmission lines [4], especially in the millimeter-wave and microwave frequencies. For a given value of a maximum reflection coefficient, it is generally acknowledged that the Klopfenstein taper produces the shortest impedance matching section (i.e., shortest transition region) in comparison, for example, to exponential or linear tapers.[5] For instance, Lee et al. discloses a transition region for use between an input stage and a radiating region in a slot line radiating element including flattened conductors fed by a coaxial cable.[6] As another example, Drabeck et al. provides an impedance matching, electrical circuit between a diode and an antenna for use in the RF frequencies.[7] Also, Hashemi-Yeganeh discloses a broadband microstrip to parallel plate waveguide transition including a metallic taper in a direction perpendicular to the substrate.[8] It is noted, however, that Hashemi-Yeganeh does not consider the rotation of electromagnetic field oscillation direction in transitioning between different transmission modes. Applicants are unaware of any work regarding the optimization of a transition region for impedance matching and/or change in mode of electromagnetic wave propagation.
The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.